<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="./demo.css">
</head>
<body>
    <!-- <img src="./star.gif" alt=""> -->
    <div><span></span></div>
    <button>重新开始</button>
</body>
<script src="./demo.js">
  

</script>
</html>